Three projects and two cores make up this competing renewal program project grant application to study mechanisms of effect of novel immunotherapeutics used to treat animal models of autoimmune disease. The studies described within this application will study two novel immunotherapies (adoptive cellular gene therapy and DNA vaccination) in two animal models of autoimmune diseases (CIA and EAE) as well as attempt to understand the mechanism(s) of successful therapeutic intervention. These therapies are poised to enter clinical trials once mechanistic understanding of effect has been demonstrated. Adoptive cellular gene therapy (Project 1) using T cell hybridomas or dendritic cells as vehicles to deliver various regulatory proteins expressed as transgenes has been proposed. Three specific aims in this project will allow vector development and adaptation of vehicle technology from T cells to autologous dendritic cells as well as studies designed to understand the mechanisms of effect. Innovative therapy will also be studied using a novel model of the application of an immuno-inhibitory GpG-ODN in vaccination models, with a single base switch from CpG to GpG, that can effectively inhibit the immuno-stimulatory response of its CpG-ODN counterpart (Project 3). Moreover, this inhibitory GpG-ODN is capable of suppressing the disease severity of experimental autoimmune encephalomyelitis (EAE) in mice by apparently inducing a Th2 shift, much as DNA co-vaccination with genes encoding myelin and IL-4. Mechanistic analysis of therapeutic intervention in both models will be studied using mRNA microarray, proteomics and intracellular assays of protein expression (Project 2). It is hoped that the combination of these approaches, integrating state of the art technology, will speed mechanistic understanding, thus human trials. Well-described interactions among the three investigators during the past funding period as well as current innovative projects and appropriate use of the animal and administrative cores are outlined in the text.